Search

The optimal design of repeaters for current-mode (CM) nano-interconnects is conducted and compared with that for voltage-mode (VM) ones. Both Cu and carbon nanotube (CNT) nano-interconnects are considered and studied, with the contact resistance treated appropriately. In comparison with the VM ones, the CM nano-interconnects can not only demonstrate better electrical performance, but also require fewer repeaters, thereby saving more valuable chip area. In the delay-optimal repeater design of multi-walled CNT interconnects, for instance, the optimal number of repeaters can be reduced by 120% with the implementation of CM signalling scheme.

N-substituted bis(diphenylphosphanyl)amine RN(PPh 2 ) 2 (PNP; R = CH 2 CH 2 CH 2 Si(OEt) 3 ) and its mononuclear nickel(II) ethanedithiolate complexe RN(PPh 2 ) 2 Ni(SCH 2 CH 2 S) (PNS; R = CH 2 CH 2 CH 2 Si(OEt) 3 ) were prepared and used as multi-element flame retardants for epoxy resin (EP). Results of thermogravimetric analysis (TGA) revealed that the incorporation of PNP or PNS restrained the decomposition of EP and also improved the stability of char residues. Moreover, results of limited oxygen index (LOI), vertical burning test (UL-94), microscale combustion calorimeter (MCC), and cone calorimeter tests proved that both PNP and PNS endowed EP with good flame retardancy. Different chemical structures and action mechanisms of PNP and PNS resulted in different degrees of flame retardancy for EP. Although EP/PNP samples caused a little higher LOI values than those of EP/PNS ones, the incorporation of 7 wt% PNS endowed EP with a lower peak of heat release rate (PHRR) and total smoke production (TSP), thereby indicating better flame-retardant and smoke suppression effects. Furthermore, thermogravimetry-Fourier transform infrared spectroscopy (TG-FTIR) and pyrolysis gas chromatography/mass spectrometry (Py-GC/MS) were employed to analyze the pyrolysis behavior of EPs and flame retardants. The morphologies of char layers for EPs were examined by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). In comparison to PNP, PNS promoted the formation of a stronger protective char barrier comprising by P/Si/S/Ni elements and also restrained the effects of flammable gases on EP.

In this study, a heat source model designed explicitly for rectangular laser heat sources was developed to simulate the temperature field during the laser hot wire cladding process. The influence of the temperature field on the solidified microstructure was investigated. The difference in morphology and size of solidified microstructure was mainly caused by temperature gradient and cooling rate. The grain morphology in the edge region was mainly columnar crystal with small size. The grain morphology in the central area was mainly equiaxed crystals with the larger size. This study provided a reference for understanding the characteristics of the solidification microstructure and its formation during laser hot wire cladding process.

With the continuous reform of China’s higher education and the increasing market demand for English professionals, the traditional college English teaching model has been unable to adapt to the development of the new era. In order to strengthen the training of application-oriented talents for college English majors, it has become an important task to reform the traditional English teaching mode. In the traditional teaching of college English major, it is necessary to add the participatory teaching mode. This paper mainly introduces definitions, characteristics, impacts on teachers and influences on students of two kinds of teaching modes. It also analyzes the differences of two kinds of teaching modes as well as how to combine two teaching modes and how to complement each other in order to achieve the perfect combination, making due contribution for training applied talents for English majors, adapting the time requests and making the college English teaching keep pace with the times.

In this paper, the optimal repeater number and size are analyzed for multi-walled carbon nanotube interconnects by using the particle swarm optimization (PSO) algorithm. Genetic algorithm (GA) is also used to verify the corresponding results. Further, the neural network (NN) is trained to facilitate the EDA process. It is found that the computational time can be dramatically reduced with the implementation of NN.

Cornstalk is usually directly used as a reductant in reductive leaching manganese. However, low utilization of cornstalk makes low manganese dissolution ratio. In the research, pretreatment for cornstalk was proposed to improve manganese dissolution ratio. Cornstalk was preprocessed by a heated sulfuric acid solution (1.2 M of sulfuric acid concentration) for 10 min at 80°C. Thereafter, both the pretreated solution and the residue were used as a reductant for manganese leaching. This method not only exhibited superior activity for hydrolyzing cornstalk but also enhanced manganese dissolution. These effects were attributed to an increase in the amount of reductive sugars resulting from lignin hydrolysis. Through acid pretreatment for cornstalk, the manganese dissolution ratio was improved from 50.14% to 83.46%. The present work demonstrates for the first time the effective acid pretreatment of cornstalk to provide a cost-effective reductant for manganese leaching.

Permafrostregions have harsh climate conditions, continuous low temperature, abrupt cooling, large temperature difference, winds, etc. It has an extremely obvious influencetoasphalt pavement structures and materials. Take Lhasa-Gongga airport highway as an example to analyze the low temperature cracking problem of asphalt pavement caused by the climatic conditions. Using finite element method to contrast and analyze the thermal stresses variation of different asphalt layer, and recommend suitable asphalt pavement structure for Qinghai-Tibet plateau permafrost regions.The results indicate that the thermal stresses of asphalt layer gradually reduce along with the thickness direction of structure, moment of maximum and minimum value also been delayed and thermal stresses of base cause is fairly few. It can reduce thermal stresses of base cause and asphalt layer effectively while using the AC-25, and 4cmAC13 + 6cmAC20 + 8cmAC25 is recommended for Lhasa-Gonggaairport highway pavement structure type.

Objective To investigate the role of B-cell-specific Moloney murine leukemia virus integration site 1 (Bmi-1) in gastric cancer (GC) and its relationship with the clinicopathological features of GC. Methods Laser capture microdissection combined with real-time polymerase chain reaction and Western blot were used to determine the expressions of Bmi-1, the cellular homologue of avian myelocytomatosis virus (c-Myc), enhancer of Zeste homolog 2 (EZH2), phosphatase and tensin homologue (PTEN) and epithelial cadherin (E-cadherin) in 20 GC specimens and the adjacent non-cancerous gastric tissues. Results The mRNA and protein expressions of Bmi-1 in GC were increased compared with those of the non-cancerous gastric tissues (P = 0.012 and P = 0.000, respectively). Bmi-1 mRNA expression was positively correlated with tumor size, degree of tumor differentiation, invasion and lymph node metastasis. At both mRNA and protein levels, Bmi-1 was positively correlated with c-Myc and EZH2, but negatively correlated with PTEN and E-cadherin. Conclusion Bmi-1 might be involved in GC at both transcription and translation levels.

The effects of geometrical and rotational isomerism on two-photon absorption (TPA) for several X-shaped molecules, each consisting of a pair of donors and acceptors, have been investigated employing the quadratic response theory with both the B3LYP and CAM-B3LYP functionals. The solvent effects on the simulated spectra are considered by means of the polarizable continuum model (PCM). Conformational Maxwell–Boltzmann (MB) averaging is carried out for rotational isomers. Our calculations exhibit that the geometrical isomers possess quite different TPA properties including the spectral profile, peak position and intensity. The rotational isomerism has unnegligible effects on the absorption position and intensity.

This paper presents a fan clutch driven by SMA spring actuator. Based on shape memory effect of SMA, the operational principle of the fan clutch driven by SMA is introduced. The equation of the output displacement of SMA actuator in free stroke is derived. The normal pressure between driving and driven discs of the clutch generated by SMA actuators is analyzed to compute the torque transmission ability in the disc-type fan clutch. The characteristic of transmission torque is studied in detail. The results indicate that the change of temperatures has a tremendous influence on the normal pressure between driving and driven discs of the fan clutch, and the transmission torque of the fan clutch changes rapidly according to the temperatures of airflow from radiator.

One- and two-photon absorption properties of organic chromophores consisting of interacting dipolar branches have been studied using density functional response theory in combination with molecular dynamics simulation. Effects of dipole interaction on optical absorptions have been examined. The importance of solvent effects on optical properties of charge-transfer states is explored by means of polarizable continuum model. It is found that for the interacting dipolar molecule with flexible conformations in solutions, the structural fluctuations can result in new spectral features or significant broadening of one-photon absorption spectrum. Our study highlights again the usefulness of the combined quantum chemical and molecular dynamics approach for modeling two-photon absorption materials in solutions.

To investigate the role of B-cell-specific Moloney murine leukemia virus integration site 1 (Bmi-1) in gastric cancer (GC) and its relationship with the clinicopathological features of GC.Laser capture microdissection combined with real-time polymerase chain reaction and Western blot were used to determine the expressions of Bmi-1, the cellular homologue of avian myelocytomatosis virus (c-Myc), enhancer of Zeste homolog 2 (EZH2), phosphatase and tensin homologue (PTEN) and epithelial cadherin (E-cadherin) in 20 GC specimens and the adjacent non-cancerous gastric tissues.The mRNA and protein expressions of Bmi-1 in GC were increased compared with those of the non-cancerous gastric tissues (P = 0.012 and P = 0.000, respectively). Bmi-1 mRNA expression was positively correlated with tumor size, degree of tumor differentiation, invasion and lymph node metastasis. At both mRNA and protein levels, Bmi-1 was positively correlated with c-Myc and EZH2, but negatively correlated with PTEN and E-cadherin.Bmi-1 might be involved in GC at both transcription and translation levels.

Mina53 is a direct novel target protein of Myc. The present study investigated the expression of mina53 and c-myc in gastric carcinoma and the relationship between Mina53 expression and clinicopathological features. The expression levels of mina53 and c-myc mRNA and protein in gastric cancers and the adjacent normal tissues from 12 patients were assessed by laser-capture microdissection (LCM) combined with quantitative polymerase chain reaction (qPCR) and western blotting, respectively. Immunohistochemical analysis was used to evaluate the expression of the Mina53 protein in normal gastric tissues (n=30), chronic atrophic gastritis without intestinal metaplasia (n=44), intestinal metaplasia (n=34), gastric dysplasia (n=36), intestinal-type gastric carcinoma (IGC) (n=30) and diffuse-type gastric carcinoma (DGC) (n=34). The correlation between expression of mina53 and patient survival time was also investigated. The expression levels of mina53 and c-myc mRNA in the gastric carcinomas were found to be higher when compared to these levels in the adjacent normal tissues. In addition, the expression levels of Mina53 and c-Myc protein in gastric carcinomas were higher when compared with levels in the adjacent normal epithelium. mina53 expression was significantly increased during gastric carcinogenesis and was correlated with different clinicopathological factors in IGC and DGC. The prognosis of patients with low expression of Mina53 was more favorable when compared to the prognosis of patients with high expression of Mina53. mina53 expression was gradually elevated during gastric carcinogenesis, and the overexpression of mina53 was correlated with different clinicopathological features between DGC and IGC cases. Furthermore, the prognosis of gastric carcinoma patients was significantly correlated with the expression of Mina53.